Enough experience has now been accumulated to conclusively demonstrate the limitation of escape equipment provided for personnel working on offshore platforms. Much of the past and present safety provisions have been biased toward providing escape craft supported at the sea surface, such as boats. This "floating lifecraft" fixation has been discredited as providing inadequate protection for personnel abandoning doomed offshore platforms.
Superficially, it appears that sturdily constructed and well-provisioned surface lifecraft, entered efficiently and launched successfully, is an effective means of preserving life. However, the violent storms destroying these platforms have claimed the lives of enough personnel to thoroughly discredit these surface crafts as havens of refuge for personnel. Of course, if the personnel can be removed from the platform, well in advance of developing life-threatening weather conditions, the problem would be solved. Boats and aircraft, employed in time, are quite effective in preserving life. It is the illusion that platforms are effectively designed to withstand the fury of cyclonic storms that has lead to the entrapment of personnel by their decision to ride out the danger of the storms. In the face of platform collapse, it is now evident that few lifecraft at the surface of the sea have been preserving a significant percentage of the lives of the personnel. Obviously, something is dreadfully wrong with the superficial assumptions that have been made to date by personnel seeking safety at the sea surface.
With safety proven non-existent at the surface of the sea, it has been suggested that refuge be sought entirely below the surface. Serious consideration has been given to the concept of transporting personnel to a location entirely below the surface. It has appeared that a system can be provided to transport threatened personnel a significant distance below the surface of the disturbed sea to provide dramatic increase for their chances of survival. Seemingly, all that was required was a change in conventional attitude to accept a submersible vessel for transporting personnel to a safe sea depth. It now appears economically chimerical to provide a life-support system for a completely submersible escape vessel.
A logical combination of the concepts embodied in surface escape craft and the concepts embodied in a completely submersible lifecraft is possible. If a lifecraft form can be provided which places the majority of its bulk a significant distance below disturbed surface conditions while providing safe access to life support surface systems, the disadvantages of both prior systems can be eliminated.